Fuel cell system and control method therefor

摘要

During an intermittent operation of the fuel cell, a demanded FC voltage calculation portion calculates a predetermined voltage that is below a heightened potential avoidance threshold voltage as a demanded FC voltage, and outputs the voltage to a converter. When during the intermittent operation of the fuel cell, a deviation obtained by subtracting a generated power of the fuel cell from a system's allowable power that is allowable in the fuel cell system becomes less than or equal to a value 0, the demanded FC voltage correction portion corrects a command value provided for the converter so that the deviation becomes equal to the value 0.

主权项

1. A fuel cell system that includes a fuel cell and a secondary cell, and that supplies electric power to a load, comprising:
a converter that controls output voltage of the fuel cell; and a high-potential avoidance control portion that restrains output voltage of the fuel cell from becoming greater than or equal to a predetermined heightened potential avoidance threshold voltage that is lower than an open-circuit voltage of the fuel cell by controlling a command value provided for the converter during an intermittent operation of the fuel cell, wherein the high-potential avoidance control portion includes a converter command value correction portion that corrects the command value for the converter so that a deviation obtained by subtracting a generated power of the fuel cell from a system's allowable power that is allowable in the fuel cell system becomes equal to a value 0 when the deviation is below the value 0, wherein a demanded fuel cell voltage setting portion that sets a predetermined voltage that is below the predetermined heightened potential avoidance threshold voltage, as a demanded fuel cell voltage, wherein a voltage correction value calculation portion that, when the deviation is less than or equal to zero, calculates a voltage correction value MV that is an amount of operation for causing the fuel cell generated power to be equal to the system's allowable power, and when the deviation exceeds zero, set a voltage correction value MV at zero, and wherein a converter command voltage output portion that outputs a value obtained by adding a demanded fuel cell voltage Vrf set by the demanded fuel cell voltage setting portion to the voltage correction value MV as a converter command voltage to the converter.